/*
 * Copyright 2013-2018 Lilinfeng.
 *  
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *  
 *      http://www.apache.org/licenses/LICENSE-2.0
 *  
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package main.java.com.waylau.netty.demo.privateprotocol.client;

import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import main.java.com.waylau.netty.demo.privateprotocol.struct.Header;
import main.java.com.waylau.netty.demo.privateprotocol.struct.NettyMessage;
import main.java.com.waylau.netty.demo.privateprotocol.util.MessageType;

import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;

import com.alibaba.fastjson.JSON;

/**
 * @author Lilinfeng
 * @date 2014年3月15日
 * @version 1.0
 *
 * 1、 这些类都是单例的
 * 2、 这里搞一个定时器5s发送一次心跳
 * 3、 如果连续发送心跳包没有接收到应答会怎样
 * (服务端和客户端需要设置超时无响应异常)
 *
 */
public class HeartBeatReqHandler extends SimpleChannelInboundHandler<Object> {

	private volatile ScheduledFuture<?> heartBeat;

	@Override
	public void channelRead0(ChannelHandlerContext ctx, Object msg) throws Exception {
		NettyMessage message = JSON.parseObject((String) msg, NettyMessage.class);
		// 握手成功，主动发送心跳消息
		if (message.getHeader() != null && message.getHeader().getType() == MessageType.LOGIN_RESP.value()) {
			heartBeat = ctx.executor()
					.scheduleAtFixedRate(new HeartBeatReqHandler.HeartBeatTask(ctx),
							0, 5000, TimeUnit.MILLISECONDS);
		} else if (message.getHeader() != null && message.getHeader().getType() == MessageType.HEARTBEAT_RESP.value()) {
//			System.out.println("服务端应答心跳 ---> " + message);
		} else {
			ctx.fireChannelRead(msg);
		}
	}

	private class HeartBeatTask implements Runnable {
		private final ChannelHandlerContext ctx;

		public HeartBeatTask(final ChannelHandlerContext ctx) {
			this.ctx = ctx;
		}

		@Override
		public void run() {
			NettyMessage heatBeat = buildHeatBeat();
//			System.out.println("Client send heart beat messsage to server : ---> " + heatBeat);
			ctx.writeAndFlush(JSON.toJSONString(heatBeat));
		}

		private NettyMessage buildHeatBeat() {
			NettyMessage message = new NettyMessage();
			Header header = new Header();
			header.setType(MessageType.HEARTBEAT_REQ.value());
			message.setHeader(header);
			return message;
		}
	}

	@Override
	public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
		// 连续50s没有响应 会出现请求超时异常
		cause.printStackTrace();
		if (heartBeat != null) {
			// 取消发送
			heartBeat.cancel(true);
			heartBeat = null;
		}
		ctx.close();//主动断开连接
//		ctx.fireExceptionCaught(cause);
	}
}
